JP2002307755A - Print system using pigment-based ink, printing method and printed matter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce unevenness of gloss on the surface of a printed matter using a pigment-based ink. SOLUTION: The part where adhesion of ink varies abruptly is eliminated by suppressing an extremely bright or dark color of image data so that the lightness does not vary abruptly. Alternatively, reflectivity on the surface of a printed matter is brought close to that of ink by improving the ink material or the surface material of the printed matter. Alternatively, ink is rendered to be absorbed easily into the printed matter by atomizing the pigment particles of ink or making fine holes in the surface of the printed matter. Alternatively, transparent (N) ink or white (W) ink is applied to a white area applied with no colored ink of CMY. Alternatively, the print face is covered with a coat layer by spraying coating agent to the surface of the printed matter or pasting a coat film thereto. Alternatively, reflection of light is prevented by forming micro protrusions and recesses on the print face of the printed matter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in printing technology using a pigment-based ink.

[0002]

2. Description of the Related Art Digital printers for printing an image formed of ink dots on a print medium based on digital image data are widely used as peripheral devices for computers and printers for digital cameras. The image quality of printed matter output by a digital printer has steadily improved, and in particular, the image quality of printed matter output by an ink jet printer has become comparable to that of silver halide photographs. With the improvement of the printing quality of such a printer and the improvement of the photographing performance of a digital camera, recently, the printed matter by the printer has been used for the purpose where silver halide photography was conventionally used. Is coming. For example, even in a photo studio where silver halide photography has been completely devoted to the past, services of photographing with a digital camera and printing with a digital printer are becoming widespread. The advantages that digital image data can be easily photo-retouched and can be distributed on a communication network are also factors that make digital printers preferred.

[0003] One of the weaknesses that has been pointed out in the past with respect to printed matter by digital printers, particularly printed matter using dye-based ink, is that light resistance is lower than that of silver halide photographs. However, improvements in inks and print media have significantly improved lightfastness. In particular, the lightfastness of printed matter by an inkjet printer using a recent pigment-based ink,
According to the test results, it is well over 100 years, completely surpassing silver halide photography. Therefore, an ink jet printer using a pigment-based ink will be widely used for printing long-life, high-quality photographs.

[0004]

When a printed matter by an ink jet printer using a pigment-based ink and a printed matter by a silver halide photograph or an ink jet printer using a dye-based ink are compared with the naked eye, a silver halide photograph and a silver halide photograph are compared. The printed matter using the dye-based ink has a constant gloss over the entire surface, whereas the printed matter using the pigment-based ink has
Although slightly, gloss unevenness exists. That is, in a printed matter using a pigment-based ink, if there is a very dark object or a shadow in a very light background, or if there is a very bright highlight spot in a very dark background, the (viewing angle) (Depending on the lighting conditions), the darkest object or shadow as a whole, or the part where the brightness changes suddenly, such as the contour of a very dark object or shadow, is less visible than other areas. May look shiny. The slight gloss unevenness may give the viewer a slightly unnatural impression.

Accordingly, it is an object of the present invention to reduce gloss unevenness on the surface of a print using a pigment-based ink.

[0006]

According to a first aspect of the present invention, there is provided a printing system which corrects original image data so as to prevent a sudden change in brightness, and generates a pigment ink based on the corrected image data. Means for performing printing by using the image forming apparatus.

[0007] In a preferred embodiment, the correcting means is configured to perform (1)
Brightness suppression that corrects the lightness near the highest value of the range of lightness to lightness that is less than or equal to a predetermined upper limit, and (2) the lightness near the lowest value of the lightness range that is higher than or equal to a predetermined lower limit. At least one of the following:

[0008] A printing method according to a second aspect of the present invention includes a step of correcting original image data so as to prevent a sudden change in brightness, and a step of performing printing using pigment ink based on the corrected image data. Performing.

A printing medium for a pigment-based ink according to a fourth aspect of the present invention has innumerable micropores on its surface for absorbing pigment particles contained in the pigment-based ink.

According to a fifth aspect of the present invention, there is provided a printing system comprising: means for obtaining, from original image data, image data of a predetermined color system corresponding to a pigmented colored ink; Means for performing printing by attaching the colorless transparent ink to the area of the print medium surface where the colored ink is not attached, using the pigmented colored ink and the substantially colorless transparent ink based on the data. Prepare.

[0011] A set of ink cartridges according to a sixth aspect of the present invention includes an ink cartridge storing a pigmented colored ink and an ink cartridge storing a substantially colorless and transparent ink.

[0012] A printing method according to a seventh aspect of the present invention comprises the steps of obtaining, from the original image data, image data of a predetermined color system including a component color corresponding to a pigmented colored ink; Based on colorimetric image data, printing is performed using a pigment-based colored ink and a substantially colorless and transparent ink so that the colorless and transparent ink is adhered to an area of the print medium surface where the colored ink is not adhered. Performing the following.

According to an eighth aspect of the present invention, there is provided a printing system, comprising: means for obtaining, from original image data, image data of a predetermined color system including a component color corresponding to a pigmented colored ink; Means for performing printing by using a pigment-based colored ink and a white ink based on colorimetric image data to cause the white ink to adhere to an area of the print medium surface to which the colored ink is not attached. .

A set of ink cartridges according to a ninth aspect of the present invention includes an ink cartridge storing a pigmented colored ink and an ink cartridge storing a white ink.

[0015] A printing method according to a tenth aspect of the present invention includes a step of obtaining, from the original image data, image data of a predetermined color system including a component color corresponding to a pigmented colored ink; Printing based on colorimetric image data, using a pigment-based colored ink and a white ink so that the white ink is attached to an area of the print medium surface where the colored ink is not attached. .

According to an eleventh aspect of the present invention, there is provided a printing system, comprising: means for printing an image on a surface of a print medium using a pigment-based ink; Means for covering with a coat layer.

According to a twelfth aspect of the present invention, there is provided a printed matter, a print medium, an image printed on the surface of the print medium by using a pigment-based ink, and a substance covering the surface of the print medium on which the image is printed. And a colorless and transparent coat layer.

[0018] A printing method according to a thirteenth aspect of the present invention comprises the steps of: printing an image on the surface of a print medium using a pigment-based ink; Covering with a coat layer.

An apparatus for coating a printed material according to a fourteenth aspect of the present invention comprises means for forming a substantially colorless and transparent coat layer on the surface of a print medium on which an image has been printed.

A printing system according to a fifteenth aspect of the present invention comprises: means for printing an image on a surface of a print medium using a pigment-based ink; Attaching means.

A printed matter according to a sixteenth aspect of the present invention comprises a print medium, an image printed on the surface of the print medium using a pigment-based ink, and a print medium on which the image is printed. It has countless fine irregularities.

A printing method according to a seventeenth aspect of the present invention includes a step of printing an image on a surface of a print medium using a pigment-based ink, and a method of forming an infinite number of fine irregularities on the surface of the print medium on which the image is printed. Attaching step.

An apparatus for processing a printed matter according to an eighteenth aspect of the present invention includes means for forming countless fine irregularities on the surface of a print medium on which an image is printed.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1A is a cross-sectional model of a printed matter by an ink-jet printer using a dye-based ink, and FIG. 1B is a cross-sectional model of a printed matter by an ink-jet printer using a pigment-based ink. Show.

As shown in FIG. 1A, the dye-based ink 1
Penetrates well into the print medium (for example, paper) 2. On the other hand, as shown in FIG. 1B, the pigment-based ink 3 hardly penetrates into the inside of the print medium 2, and therefore, in a very dark portion (that is, a portion where the pigment ink 3 is attached very much), Islands of the pigment ink 3 are formed on the surface of the print medium 2 and thickly cover the print medium surface, completely hiding the texture of the print medium surface. The surface 2a of the very bright color portion where the texture of the print medium surface is well exposed generally has a low light reflectance, whereas the surface 3a of the island of the pigment ink 3 which is the extremely dark color portion has Due to the characteristics, the light reflectance is relatively high. Therefore, when the surface 2a having a low light reflectivity and the surface 3a having a high light reflectivity are adjacent to each other, the surface 3a in a dark portion having a high light reflectivity may look conspicuous. In addition, the surface 3b of the edge portion of the island of the pigment ink 3 (that is, the portion where the brightness changes rapidly)
Depending on the angle of viewing and the angle of light, it may be noticeable because it is only tilted. Such a difference in light reflectance on the surface of the printed matter is presumed to be the cause of gloss unevenness of the printed matter using the pigment ink.

The present invention provides several methods for reducing the difference in light reflectance on the surface of a printed material using a pigment ink or making the difference in light reflectance less noticeable to a viewer. These methods can be classified as follows.

(1) By processing an image and correcting its density, a sudden change in the light reflectance on the surface of the printed matter is mitigated.

(2) By improving the material of the ink or the material of the surface of the print medium, the difference in light reflectance due to the amount of ink adhered to the surface of the print medium is reduced.

(3) The difference in light reflectance on the surface of a printed material is reduced by improving the use of ink for expressing the density.

(4) The difference in light reflectance is reduced by applying a coating on the surface of the printed material.

(5) The difference in light reflectance is reduced by machining the surface of the printed material.

These techniques can be used alone or
They can be used in an appropriate combination.

Hereinafter, embodiments of these techniques will be described.

FIG. 2 shows the configuration of a printing system using a pigment-based ink jet printer according to an embodiment of the above-described image processing method (1).

As shown in FIG. 2, original image data 4 such as, for example, RGB full-color image data is input to a color conversion unit 5, where color system conversion processing and lightness correction processing, which will be described later, are performed. The image data 6 output from the color conversion unit 5 is input to a halftoning unit 7. The half-toning unit 7 performs a process such as error diffusion or dithering on the input image data 6 so that the multi-tone density of each of the CMY colors of the input image data 6 is determined by the density of the ink dots of each of the CMY colors. Substantially faithfully expressed eg 2
It generates bitmap image data 8 that has been converted into a value. The bitmap image data 8 output from the halftoning unit 7 is transferred to the print head 9. The print head 9 prints an image by forming dots of pigment-based ink on the surface of a print medium according to the bitmap image data 8.

As described above, the color conversion section 5 performs the color system conversion processing and the brightness correction processing on the input original image data 4.

In the color system conversion processing, the original image data 4, for example, RGB color system color data is converted into, for example, CMY (or CMYK, CMYLCLMLYK, etc.) containing component colors corresponding to the color set of the pigment ink used in printing. ) The color data is converted into color data.

The lightness correction processing is performed before or after the color system conversion processing or during the color system conversion processing. In this processing, the color data constituting the original image data 4 has The lightness (that is, the value corresponding to the L component when expressing the color data in the Lab color system) is corrected as follows. That is, in this brightness correction processing, color data having extremely high brightness in the original image data is corrected to color data having lower brightness (hereinafter, this correction is referred to as “brightness suppression”). Alternatively, in the color level correction processing, color data having extremely low brightness in the original image data is corrected to color data having higher brightness (hereinafter, this correction is referred to as “dark portion suppression”). The above high brightness suppression and dark area suppression are
Either one or both may be performed.

FIG. 3 shows an example of input / output characteristics of the brightness correction processing. In FIG. 3, the horizontal axis indicates the brightness (input brightness) of the color data of the original image data, and the vertical axis indicates the brightness (output brightness) of the corrected color data. The brightness can take a value of 0 to 255, for example.

A curve a or b shown in FIG. 3 is an example of an input / output function for performing the above-described bright portion suppression, in which an extremely high (for example, near the maximum value 255) input brightness is converted to a predetermined upper limit A
(Eg, 250). Also,
The curve c or d is obtained by adding the function of suppressing a dark part to the curve a or b, and is extremely low (for example, near the minimum value 0).
The input brightness is converted to an output brightness higher than a predetermined lower limit B (for example, value 5).

By the above-described bright portion suppression, an extremely bright portion such as a highlight spot in the original image is corrected to a slightly darker color. Further, by the above-described dark part suppression, an extremely dark part in the original image is converted into a slightly brighter color. By performing one or both of the bright part suppression and the dark part suppression, the lightness of the part where the lightness suddenly changes in the original image is corrected so as to change more gently. Therefore, on the surface of the output printed matter, a sudden change in the amount of ink attached (that is, a sudden change in light reflectance) is reduced,
It will change somewhat slowly. As a result, the feeling of straying where the ink is attached a lot,
It becomes difficult for human eyes to recognize, and uneven gloss becomes less noticeable. The input / output characteristic curve for bright part suppression or dark part suppression as illustrated in FIG. 3 may be adjusted manually by the user or automatically by the system according to the target image data.

Next, an embodiment of the method (2) by improving the ink material or the surface material of the print medium will be described.

One embodiment is a printing method using an ink in which the size of pigment particles is extremely fine and uniform. Since the pigment particles contained in the ink are extremely fine, the penetrability of the ink into the print medium is improved, and the island of the ink 3 as shown in FIG. To reduce.

Another embodiment is a printing method using a printing medium having a surface on which countless micropores for absorbing pigment particles of ink are formed. Thereby, the permeability of the ink into the print medium is improved, and the island of the ink 3 as shown in FIG. 1 is prevented from being formed on the surface of the printed material, and the gloss unevenness is reduced.

Still another embodiment is a printing method using an ink in which the light reflectance of the ink in a dry state is lower than the conventional one and is close to the light reflectance of the print medium surface. As a result, gloss unevenness on the surface of the printed material due to the difference in the amount of ink adhesion is reduced.

Still another embodiment is a printing method using a printing medium in which the light reflectance of the surface of the printing medium is higher than before and is close to the light reflectance of the ink in a dry state. As a result, gloss unevenness on the surface of the printed material due to the difference in the amount of ink adhesion is reduced.

Next, an embodiment of the method (3) in which the use of ink for expressing colors is improved will be described.

FIG. 4 shows an embodiment in which colors are expressed using substantially colorless and transparent ink (indicated by the symbol “N”) in addition to general colored inks such as CMY.
1 shows a configuration of a print system using a pigment-based inkjet printer.

As shown in FIG. 4, original image data 10 such as RGB full-color image data is
Is input to The color conversion unit 11 converts the input color data of the original image data 10 into, for example, RGB color system data into, for example, CMY (or CMYK, CMYLCLMLYK, or the like) having color components corresponding to the color set of the color ink used in printing. Good) Convert to color data of color system. The image data 12 output from the color conversion unit 11 is input to a halftoning unit 13. The half-toning unit 13 performs a process such as error diffusion or dither on the input image data 12 so that the density of the multi-tone (for example, 256 tones) of each CMY color of the input image data 12 can be converted into the CMY color inks. For example, binarized bitmap image data 14 that is expressed substantially faithfully by the dot density is generated.

When generating the bitmap image data 14, the halftoning unit 13 generates N dot data indicating colorless and transparent (N) ink dots in addition to CMY dot data indicating CMY dots. According to the N dot data, when any of the C, M, or Y colored ink dots is not hit, the N ink dots are hit instead of the non-hit color ink dots. . Alternatively, according to the N dot data, N ink is attached to a bright area where the amount of attached color ink is small so as to fill the hole of the color ink. The bitmap image data 14 output from the halftoning unit 13 includes the above-described dot data of C, M, Y, and N.

The bitmap image data 14 output from the halftoning unit 13 is transferred to the print head 15. The print head 15 has a set of four sub-heads using C, M, Y and N inks respectively, and C, M, Y
And C, M, Y, and N inks are supplied from the set 15A of the N and N ink cartridges (ink tank). The print head 15 prints an image by forming dots of C, M, Y, and N inks on the surface of the print medium in accordance with the transferred bitmap image data 14.

FIG. 5 shows a cross-sectional model of a printed matter output according to this embodiment.

As shown in FIG. 5, in addition to the color ink 17 adhering to the surface of the print medium 16, a colorless and transparent (N 3.) Ink 18 adheres. As a result, the amount of ink adhered to the surface of the print medium 16 becomes nearly uniform, and the difference in light reflectance, that is, the unevenness in gloss is reduced.

FIG. 6 shows a pigment-based ink jet printer according to an embodiment in which colors are expressed using white (indicated by "W") ink in addition to general colored inks such as CMY. 1 shows the configuration of the print system that was used.

As shown in FIG. 6, original image data 20, such as RGB full-color image data, is
Is input to The color conversion unit 21 converts, for example, RGB colorimetric color data constituting the input original image data 20 into, for example, CMYW including color components corresponding to, for example, C, M, Y, and W ink sets used in printing. (Or CMYKW, CMYLCLML
(It may be YKW, etc.) Convert to color data of color system. Here, the color data of the CMYW (or CMYKW, CMYLCLMLYKW, etc.) color system is obtained by replacing color data in which the densities of C, M, and Y are all 0% with color data in which only W has a density of 100%. Based on the principle that a bright color can be created by mixing a W pigment with another colored pigment, such as a color mixing technique of a painting or an oil painting, for example, the W color component is added to the C, M, and Y color components. In addition, it is color data expressing a color with particularly high brightness. That is, the conventional method of using ink in a printer is based on the principle that brightness is obtained by not using ink, whereas CMYW (or CMYKW, CMYLCL) is used.
The method of using the color system ink is based on the principle that the W ink is used positively to generate brightness.

The image data 22 of the CMYW color system output from the color conversion unit 21 is input to a halftoning unit 23. The halftoning unit 23 performs, for example, error diffusion or dither processing on the input CMYW color system image data 22 to convert, for example, binarized bitmap image data 24 representing dots of each CMYW color ink. Generate. The bitmap image data 24 output from the halftoning unit 23 is transferred to the print head 25. The print head 25 has a set of four sub-heads using inks of C, M, Y and W, respectively, and sets C, M, Y and W of ink cartridges (ink tanks) 25A to C, M, Y and W. Ink supply. The print head 25 prints an image by forming dots of C, M, Y, and W inks on the surface of the print medium in accordance with the transferred bitmap image data 24.

According to this embodiment, C,
In areas where the M and Y colored inks are not attached, instead of W
Since the ink adheres, the amount of the ink adhered on the print medium surface becomes nearly uniform, and the difference in light reflectance, that is, the unevenness in gloss is reduced.

Next, an embodiment of the method (4) for coating a printed material surface will be described.

FIG. 7 shows the configuration of a printing system using a pigment-based ink jet printer according to an embodiment of the present invention.

As shown in FIG. 7, the print medium 30 is intermittently fed by paper feed rollers 31 in the direction of arrow 32 in the figure. While the paper is being fed, the print head 33 travels near the surface of the print medium 30 in a direction penetrating the paper in FIG.
The image is printed on the surface of the print medium 30 by being attached to the surface of the print medium 30.

A coating head 35 exists downstream of the print head 33 in the paper feed direction. The coating head 35 applies a quick-drying liquid substantially colorless and transparent coating agent on the printing surface of the printing medium 30 while traveling near the printing surface of the printing medium on which printing has been completed in a direction penetrating the paper of FIG. Spray in a uniform amount. Alternatively, the coating head 35 extends over the entire width of the print medium 30 and sprays the coating agent over the entire width of the print surface of the print medium 30 simultaneously in a uniform amount. The coating agent sprayed on the print surface of the print medium 30 immediately dries to form a colorless and transparent coat layer completely covering the printed image.

In FIG. 7, the coating head 35
Although the print head 33 and the print head 33 are separate components, the coating head 35 and the print head 33 may be an integral component and run together by a carriage. Further, the coating head 35 includes a printing head 33.
It is not necessarily required to be incorporated in the same printer as that described above, and even if it is a separate device separated from the printer and the printed matter output from the printer is supplied to the coating head 35 manually or automatically. Good. The coating head 35 does not necessarily need to spray a liquid coating agent, but sprays a heat-soluble powder coating agent onto a print medium, and then heat-treats the powder coating agent to form a layer by dissolving the powder coating agent. It may be one that generates a mist of the coating agent by ultrasonic waves and attaches it to the print medium surface, or one that causes the mist of the coating agent to adhere to the print medium surface by electrostatic adsorption. The coating medium may be applied, a liquid coating agent may be applied to the surface of the print medium, or the print medium surface may be immersed in a liquid of the coating agent. Various other configurations may be employed.

FIG. 8 shows a printing system using a pigment-based ink jet printer according to another embodiment of the coating method.

In FIG. 8, as in FIG.
0 is intermittently fed by the paper feed rollers 31, 31 in the direction of arrow 32 in the figure. In the interval between paper feeds, print head 3
3, while traveling near the surface of the print medium 30 in a direction that penetrates the paper in the figure, ejects ink droplets as indicated by arrows 34 and adheres to the surface of the print medium 30, whereby an image is formed on the surface of the print medium 30. Is printed.

A roller mechanism 3 for affixing a colorless and transparent coat film 37 over the entire printing surface of the printed printing medium downstream of the print head 33 in the paper feed direction.
8, 38 exist. The roller mechanisms 38, 38 draw out the roll-shaped coat film 37, overlap the rolled coat film 37 over the entire printing surface of the printed printing medium, and press the both while applying heat from the outside. The coat film 37 is a substantially colorless and transparent, for example, thermoplastic synthetic resin film, and when pressure and heat are applied, the coat film 37 is attached to the print surface of the print medium to form a coat layer that completely covers the print image.

The coating film 37 and the roller mechanism 3
The portions 8 and 38 need not be incorporated in the same printer as the print head 33, but are separate devices separated from the printer, and the printed matter output from the printer can be manually or automatically supplied to the roller mechanism 38. , 38. Coat film 37
Does not necessarily have to be in the form of a roll, and may be cut into a required size in advance.

FIG. 9 shows a cross-sectional model of a printed matter output by the embodiment of FIG. 7 or FIG.

As shown in FIG. 9, the coat layer 42 on the surface of the print medium 40 completely covers both the portion where the ink 41 has adhered and the portion where the ink 41 has not adhered. , The light reflectance is uniform and there is almost no problem of gloss unevenness.

Next, an embodiment of the method (5) for performing machining on the surface of a printed material will be described.

FIG. 10 shows the configuration of a print system using the pigment-based ink jet printer according to this embodiment.

As shown in FIG. 10, the print medium 43 is intermittently fed in the direction of arrow 49 in FIG. While the paper is being fed, the print head 45 travels near the surface of the print medium 43 in a direction penetrating the paper in FIG.
An image is printed on the surface of the print medium 43 by attaching the image to the surface of the print medium 43.

Roller mechanisms 47 and 48 are provided downstream of the print head 45 in the paper feed direction to make countless fine irregularities on the entire print surface of the print medium 43 on which printing has been completed. The entire surface of the roller mechanism 47, which is in contact with the printing surface, of the roller mechanisms 47, 48 has countless fine irregularities. When the print medium 43 passes through the roller mechanisms 47, 48, the roller 47 Is pressed against the print surface of the print medium 43 with a strong pressure, and countless fine irregularities are imprinted on the entire print surface. The size of the fine irregularities is such that when a person looks at the surface of the print medium on which it is engraved, light is substantially perceived as irregularly reflected (that is, the semi-glossy surface is (For example, the diameter or width of each unevenness is about 0.5 mm or less). Various shapes such as a dot shape, a stripe shape, a stripe shape, and a lattice stripe shape can be adopted as the shape of the individual unevenness.

The roller mechanisms 47 and 48 do not necessarily need to be incorporated in the same printer as the print head 45, but are separate devices separated from the printer, and prints output from the printer are manually or automatically. Alternatively, it may be supplied to the roller mechanisms 47 and 48.

FIG. 11 shows a cross-sectional model of a printed matter output according to the embodiment of FIG.

As shown in FIG. 11, the surface of the print medium 50 has a portion where the ink 41 is attached and a portion where the ink 41 is not attached.
Since the light impinging on this surface is substantially irregularly reflected because it is not flat but has countless fine irregularities, the entire surface of the surface looks like a semi-glossy surface. Further, the island of the ink 51 is also pushed and pushed into the print medium 50 to some extent, and the height thereof is not much different from the portion where the ink 41 is not attached. As a result, the difference in light reflectance on the surface of the print medium 50, that is, the unevenness in gloss is reduced.

Although the embodiment of the present invention has been described above, this is an exemplification for describing the present invention, and is not intended to limit the scope of the present invention only to this embodiment. Therefore, the present invention can be implemented in other various forms without departing from the gist thereof.

[Brief description of the drawings]

FIG. 1A is a cross-sectional view showing a cross-sectional model of a printed matter by an ink-jet printer using a dye-based ink, and FIG. 1B is a cross-sectional view showing a cross-sectional model of a printed matter obtained by an ink-jet printer using a pigment-based ink.

FIG. 2 is a block diagram showing a configuration of an embodiment of a method based on the image processing of the above (1).

FIG. 3 is a diagram illustrating an example of input / output characteristics of a brightness correction process.

FIG. 4 is a block diagram showing a configuration of an embodiment using colorless and transparent (N) ink in addition to CMY ink.

FIG. 5 is a sectional view showing a sectional model of a printed matter output by the embodiment of FIG. 4;

FIG. 6 is a block diagram illustrating a configuration of an embodiment using white (W) ink in addition to CMY inks.

FIG. 7 is a side view showing the configuration of an embodiment of a method for applying a coating to the surface of a printed material.

FIG. 8 is a side view showing the configuration of another embodiment of a method for applying a coating to the surface of a printed material.

FIG. 9 is a cross-sectional view showing a cross-sectional model of a printed matter output by the embodiment of FIG. 7 or 8;

FIG. 10 is a side view showing a configuration of an embodiment of a technique for performing machining on the surface of a printed material.

FIG. 11 is a sectional view showing a sectional model of a printed matter output by the embodiment of FIG. 10;

[Explanation of symbols]

 4, 10, 20 Original image data 5, 11, 21 Color conversion unit 7, 13, 23 Half toning unit 15 CMYN print head 15A CMYN ink cartridge 25 CMYW print head 25A CMYW ink cartridge 35 Coating head 37 Coating film 38 Roller mechanism 47 , 48 roller mechanism

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B41M 5/00 B41J 29/00 H H04N 1/23 101 3/04 102Z (72) Inventor Masayasu Fujio Nagano 3-5-5 Yamato, Suwa-shi Seiko Epson Corporation (72) Inventor Atsushi Hatta 3-3.5-5 Yamato, Suwa-shi, Nagano F term in Seiko Epson Corporation 2C056 EA11 EC69 EC79 EE03 EE17 EE18 FA10 HA44 2C061 AQ05 AR01 CK02 CK05 CK10 2C262 AA02 AA24 AB05 AB13 BA09 BA14 BA16 BC09 EA04 EA11 2H086 BA02 BA05 BA15 5C074 AA08 BB16 BB22 BB30 CC26 DD22 DD24 DD27 FF15 HH04

Claims (18)

[Claims] 1. A printing system comprising: means for correcting original image data so as to prevent a sudden change in brightness; and means for performing printing using pigment ink based on the corrected image data. 2. The image processing apparatus according to claim 1, wherein the correcting unit calculates, for the color data included in the original image data, the following lightness in the vicinity of the highest value of the lightness range (1) and (2): Claims wherein at least one of: bright part suppression for correcting brightness below a predetermined upper limit, and (2) dark part suppression for correcting brightness near the lowest value of the range of possible brightness to brightness above a predetermined lower limit. 1. The printing system according to 1. 3. A printing method comprising: a step of correcting original image data so as to prevent a sudden change in lightness; and a step of performing printing using pigment ink based on the corrected image data. 4. A printing medium for a pigment-based ink, which has innumerable micropores on its surface for absorbing pigment particles contained in the pigment-based ink. 5. A means for obtaining image data of a predetermined color system corresponding to a pigment-based colored ink from original image data, and based on the image data of the predetermined color system, Using ink and substantially colorless and transparent ink,
Means for performing printing by adhering the colorless transparent ink to an area of the surface of the print medium where the colored ink is not adhered. 6. An ink cartridge set comprising an ink cartridge storing a pigmented colored ink and an ink cartridge storing a substantially colorless and transparent ink. 7. A step of obtaining, from the original image data, image data of a predetermined color system including a component color corresponding to a pigment-based colored ink, based on the image data of the predetermined color system, Using the pigment-based colored ink and the substantially colorless transparent ink to perform printing by attaching the colorless transparent ink to an area of the print medium surface where the colored ink is not attached. Method. 8. A means for obtaining, from the original image data, image data of a predetermined color system including a component color corresponding to a pigmented colored ink, based on the image data of the predetermined color system, Means for performing printing by using the pigment-based colored ink and the white ink so that the white ink is attached to a region of the print medium surface where the colored ink is not attached. 9. An ink cartridge set comprising an ink cartridge containing a pigmented colored ink and an ink cartridge containing a white ink. 10. A step of obtaining, from the original image data, image data of a predetermined color system including a component color corresponding to a pigment-based colored ink, based on the image data of the predetermined color system, Performing printing by using the pigment-based colored ink and the white ink so that the white ink is attached to a region of the print medium surface where the colored ink is not attached. 11. A print comprising: means for printing an image on a surface of a print medium using a pigment-based ink; and means for covering the surface of the print medium on which the image has been printed with a substantially colorless and transparent coat layer. system. 12. A print medium, an image printed on the surface of the print medium using a pigment-based ink, and a substantially colorless and transparent coat layer covering the surface of the print medium on which the image is printed. Printed material provided. 13. A print comprising: printing an image on a surface of a print medium using a pigment-based ink; and covering the surface of the print medium on which the image is printed with a substantially colorless and transparent coat layer. Method. 14. An apparatus for coating printed matter, comprising: means for forming a substantially colorless and transparent coat layer on the surface of a print medium on which an image is printed. 15. A printing system comprising: means for printing an image on a surface of a print medium using a pigment-based ink; and means for forming countless fine irregularities on the surface of the print medium on which the image is printed. 16. A printing medium, comprising: an image printed on the surface of the printing medium using a pigment-based ink; and countless fine irregularities attached to the surface of the printing medium on which the image is printed. Printed matter. 17. A printing method, comprising: printing an image on a surface of a print medium using a pigment-based ink; 18. An apparatus for processing a printed matter, comprising means for forming countless fine irregularities on the surface of a print medium on which an image is printed.